Lift truck hoisting and dumping equipment



Jan. 19, 1960 G. R. DEMPSTER ETA'- 2,921,703

LIFT TRUCK HoTsTING AND DUMPTNG EQUIPMENT 5 Sheets-Sheet 1 Filed Jan. 9, 1957 ATTORNEY Jan. 19, 1960 G. R. DEMPsTER ETAL 2,921,703

LIFT TRUCK HOISTING AND DUMPING EQUIPMENT Filed Jan. 9, 1957 5 Sheets-Sheet 2 ATTORNEYS Jan. 19, 1960 G. R. DEMPSTER ETAI- .2,921,703

LIFT TRUCK HorsTING AND DUMPING EQUIPMENT Filed Jan. 9, 1957 5 Sheets-Sheet 3 lNvENToR BY l fn/Tm;

ATTORNEYS Jan. 19, 1960 G. R. DEMPsTER ETAI- 2,921,703

LIFT TRUCK HoTsTING AND DUMPTNG EQUIPMENT 5 Sheets-Sheet 5 Filed Jan. 9, 1957 hun THM :j ||A 1. l v

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ATTORNEYS United States Patent O George R. Dempster and William A. Herpich, Knoxville,

Tenn.; said Herpich wignor to Dempster Brothers, Inc., Knoxville, Tenn., a corporation of Tennessee' Application January 9, 1957, Serial No. 633,237

14 Claims. (Cl. 214-317.)

This invention relates to improvements in lift truck hoisting and dumping equipment and more particularly to an attachment for a lift truck to transport and dump detachable containers.

Detachable containers that are adapted to be lled when sitting on the ground or on a oor or other location, have been constructed in various types, such, for example, as drop bottom containers, tilt-type containers, skip-type containers, etc. Many of these have been provided with bails adapted for engagement by automatic hooks on the transporting and dumping equipment to facilitate the dumping thereof.

Fork trucks have also been provided heretofore for picking up and transporting such containers, having the arms thereof engaging under lifting pins on the ends of the containers. Due to variations in the types of the containers and differences in the type and location of the bails on diiferent containers, it has been diicult Ito use the lift truck equipment for handling many different types of containers.

One object of this invention is to overcome these objections and to provide a lift truck attachment which will handle not only many different types of containers, but also will have provisions for dumping such containers, even though provided with dilferent types of bails.

Another object of the invention is to provide in `a container dumping attachment for a vehicle for the lowering of the automatic 'hook that engages the bail on the container to a position substantially at or very close to the ground level.

Still another object of the invention is to provide in an attachment for a lift truck for the vertical adjustment of dumping hooks with respect to the arms that support the body of the container so as to engage selectively a dumping bail connected with the body, whether the bail be located at the top or at the bottom of the container, or

at some intermediate point thereon.

A still further object of the invention is to improve the construction of the hoisting mechanism to provide a compact assembly of parts and provision for lowering of an elevator section carrying the automatic hooks, to

an abnormally low position with respect to the hoisting unit.

These objects may be accomplished, according to one embodiment of the invention, by providing, on the carriage of a lift truck, a hoisting unit which includes the usual lift forks and also a hoisting carriage on which an elevator is mounted for raising and lowering movement Ywith respect to the hoisting cam'age and the forks. The

elevator has one or more dumping hooks secured thereward to aposition where itwill engage a dumping bail,

'substantially at the bottom of the container. Hoisting 92u63 Patented Jan; 19, 196i) ,a ICC means is provided on the hoisting carriage for raising and lowering the elevator with respect thereto, but without interfering'with the lowering movement of the elevator to abnormally low position. In this way, the hoisting mechanism can accommodate containers of dilferent types, and also lifting bails of different types and locations.

This embodiment ofthe invention is illustrated in the accompanying drawings, in which:

Fig. l is a side elevation of a lift truck having the improved attachment lapplied thereto and shown with a container of one form;

Fig. 2 is a similar view, shown with a container of a different type;

Fig. 3 is a horizontal sectional view on the line 3-3 in Fig. 1;

Fig. 4 is a side elevation of the hoisting carriage detached;

Fig. S is an edge elevation thereof;

Fig. 6 is a side elevation of the elevator detached;

' Fig. 7 is an edge view at right angles thereto; and

Fig. 8 is a view on an enlarged scale of an automatic hook used on the lift truck.

The invention is shown as applied to a lift truck of conventional construction, generally indicated by the numeral 1. Such truck comprises a self-propelled motor vehicle having th'e usual forks on the front end thereof. The. forks are supported by an upright carriage, generally indicated at 2,. The carriage 2 is mounted on a pivotal support'onthe frame of the fork truck 1 for tilting movement forward and backward relative to the upright position shown in Figs. 1 and 2. This tilting movement is usually accomplished by a hydraulic cylinder 4 connected with the carriage 2. 'v

The fork truck carriage 2 includes a pair of upright spaced guides 5 and having guideways on the inner opposed faces thereof. Elevator structure, generally indicated at 6, is mounted in the guides 5 and includes a fork mounting section 7 having guide rollers 8 connected therewith operatively mounted within the elevator 6. These parts are assembled for relative raising and lowering movements by hoisting means that includes a hydraulic cylinder 9 (Fig. 3) and suitable lifting chains connected thereto and to the stationary section and fork mounting section 7 in the conventional manner of operating fork truck mechanism.

The forkV mounting section 7 is elongated transversely an 'appreciable distance and has the usual forks 10 mounted on the opposite ends thereof, shown in Figs.' l, 2 and 3. The spacing between the forks 10 should be sucient toreceive therein the usual container provided for transporting and dumping equipment, an example of whichis illustrated at C in Fig. l, land another example is illustrated at yC in Fig. 2. The container C is of the tilt-type, while the container C' is of the drop bottom type. Many other types of containers can be -used with this equipment.

Each of these containers C and C' is provided with lifting pins 11 on opposite ends thereof connected with the end walls of the container C and with the drop bottom door of the container C in the conventional construction. Each container is lalso provided with a dumping bail, as indicated at 12 in Fig. l and at 12 in Fig. 2. Some types of dumping bails are connected with the bottom portion of the container, as in Fig. l, while others are at the top thereof, as in Fig. 2. The dumping mechanism should accommodate bails in any positions with respect to the containers.

Mounted in xed relation to the fork mounting section prising a pair of laterally spaced guide channels 15 in opposed-relation and held spaced apart by a plurality of yokes 14. The carriage 13 is shown in detail in Figs. 4 and 5, wherein the-upright guide bar channels 15 are open throughout their length, including particularly the lower Vends thereof. These guide bar channelsV V15 are provided with laterally extending plates 16 adjacent the lower'ends thereof for connection therewith of the vfork mounting section 7.

At the upper endy of the fork mounting section7 are Y stirrup plates 17 extending laterally in opposite directions from ,the channels 15 upon `which are seated hydrauiic cylinders 18 that extend upwardly therefrom substantially to the upper end of the carriage 13, as indicated in dotted lines in Fig. 4. v

Operatively mounted in the carriage 13 is an elevator, generally indicated at 19, shown Aindetail in Figs. 6 and 7. The elevator 19 comprises a pair of upright channels 20 spaced apart and partially closed on the inner faces thereof by plates 21 in the intermediate and lower end portions thereof.` The channels areV guided within the guide channels 15 of the carriage 13 for vertical sliding movement relative thereto. Due to the open lower end ofthe carriage 13 between the channels 15, the elevator can project therefrom, as illustrated in Figs. l and 2, to points below the ground level where space' is available for such projecting action.

A cross bar 22 is secured upon the upper ends of the channels 20and extends outwardly beyond the outer-sides of said bars, overlapping the upper ends of the hydraulic cylinders 18. Depending tubes 23 on the under side of bar 22 at the opposite ends thereof are provided for connection with the piston rods of the cylinders 18 to firmly anchor the cylinders to the elevator. Thus, when hydraulic pressure is provided in the cylinders acting in an upward direction on the pistonsV therein, the elevator 19 is forced upward with respect to the carriage 13.

Mounted at suitable' intervals between the channel bars 20, as at an intermediate portion and at the lower end portion thereof, are blocks 24 for automatic hooks, lindicated generally at 25, pivoted to the blocks by pivot pins 26 (see Figs. l and 2). The automatic hooks 25, may be of conventional structure such as shown in the patents to Standirfer, No. 2,872,237, and to Dempster, No. 2,445,106. These hooks are usually employed for engagement with the bails of the containers, as, for example, the bails indicated at 12 and 12', respectively. Each of the automatic hooks 25 has an upward hook portion 28 with a throat in position to receive a bail and with a closure shuttle 25' pivotally mounted on the hook Vin position to close thereover and to confine the bail in the thorat.

The space between the bars 20 permits the Vhooks to hang-down between the bars and to be projected therefrom in the path of the bail or bails as the elevator is moved upward relative to the container. Two hooksuare shown, the lower hook being used for a bail provided at or adjacent the bottom portion of the container, while the upper hook is used for a bail provided adjacent the upper portion of the container, and on any type of container for which the equipment is adapted to be used. The projection of the elevator through the lower end of the hoisting carriage 13, as indicated in Figs. Vl and 2, is suicient to carry the lower hook to a point where it will engage with a bail at the bottom of the container, as indicated, for example, at 12 in Fig. l. Thus, the elevator is capable of movement throughout the length of the carriage 13 to extreme positions, which is facilitated by the disposition of'the hoisting cylinders 18 on the outer sides of the elevator and spaced outwardly, also with respect to the carriage.

In the operation of the equipment, thefork truck carriage, generally indicated at 2, is operated in the usual manner, both in propulsion and for raising and lowering of the forks 10. In normal operation, the elevator 19 must be raised with respect to the hoisting carriage 13 Vwhen'the fork section is being lowered so as to prevent damage. These forks 10 are adapted to be moved under the liftingY pins 11 on the container, being spaced the proper distance apart according to the length of the container so as to engage the lifting pins. After thus moving under the lifting pins, the fork truck carriage is operated to raise the fork mounting section 7 and thereby raise the forks 10, thus picking up the container supported thereby, preferably with the back 'of the container vbearing against the skid frame provided onthe-hoisting carriage 13. Skid bars areshown at ,27 in Fig. 3, extending upwardly along the lower end portion of this carriage for holding the back of the container in place and to permit guiding action with respect thereto.

When the container is moved or transported to the point of dumping, the elevator 19 is raised or lowered with respect tothe carriage '13 to move one of the dumping hooks into operative engagement with the bail provided on the container. If the container beingl handled has the bail at the bottom thereof, the lowermost-hook 26 is moved into Yengagement therewith, or the upper hook is used'ifthe bail'is at-or adjacent the -top of the container. The hook thus holds the body of the container againstthe skid bars 27 during the dumping actionv which is accomplished by the relative vertical movement between the Aelevator 19 and the forks 10. For example, the forks may be lowered vwhile the elevator is stationary, as indicated in dotted lines in Figs. l and 2, to accomplish a relative shifting either of the container lbody, as in Eig.' l, or of the drop bottom door with respect to the'body ofthe container, as indicated in Fig.'2, Yto discharge the contents therefrom. Then the parts are restored to their normal relation, and asthe container is moved to a still higher position with respect to its connected hook, the bail is released from lthe hook and the container may then be set back-on the groundor other point of refilling. The downward projection of the Aelevator with respect to the car- Ariage also facilitates this releasefrom the hook, especially when a lower bail is used.

'While the invention has been illustrated and described in one embodiment, it is recognized that variations and .changes may be made therein without departing from the invention as set forth in the claims.

We claim :V

l. In transporting and dumping equipment for a dumping container having a bail thereon for holding the container in place during dumping, of a pair of forks adapted for supporting engagement with the container, hoisting means for the forks, a carriage mounted in fixed relation to the forks and extending in upright position, an elevator mounted on the carriage for raising and lowering movements with respect thereto, and an automatic dumping hook on the elevator in position for lowering movement to a point below the bail and for engagement with the bail to cause dumping action of the container, said carriage including a pair of upright guide bars spaced apart transversely and mounting the elevator therebetween, said guide bars having Vthe lower ends thereof open for projecting action of the elevator downwardly through said open lower ends, and means operatively connected with the carriage for moving the hook to aY point below the forks and below the bail forrclearing the hook from the bail.

,2. ,In transporting and dumping equipment for a dump- Ving container having a bail thereon for holding the container in place during dumping, of a pair of forks adapted for supporting engagement with the container, hoisting means for the forks, a carriage mounted in fixed relation to the forks and extending in upright position, an elevator mounted on the carriage for raising and lowering` movements with respect thereto, a dumping hook on the elevator in position for lowering movement to arpoint'below the carriage and for engagement ,with the bail tol cause dumping action of the container, said carriageincluding a pair of upright guide bars spaced apart transversely and mounting the `elevator therebetween, said guide bars having the lower ends thereof open for projecting action of the elevator downwardly through said open lower end, and means for raising and lowering the elevator with respect to the caniage including a pair of cylinders mounted on the lateral outer sides of the 'carriage and 'having operative connection with the upper end of the elevator.

3. In transporting and dumping equipment for a dumping container having a bail thereon for holding the container in place during dumping, of a pair of forks adapted for supporting engagement with the container, hoisting means for the forks, a carriage mounted in fixed relation to the forks and extending in upright position, an elevator mounted on the carriage for raising and lowering movements with respect thereto, and a dumping hook on the elevator lin position for lowering movement to a point below the carriage and for engagement with the bail to cause dumping action of the container, said carriage including a pair of upright guide bars spaced apart transversely and mounting the elevator therebetween, said guide bars having the lower ends thereof open for projecting action of the elevator downwardly through said open lower end, said elevator including a pair of upright bars spaced apart in guiding relation with the carriage, a bar extending transversely of the upper end of the upright bars and secured thereto, said transverse bar extending to points beyond opposite sides of the carriage, and upright cylinders mounted on the carriage and connected with the opposite ends of said transverse bar for raising and lowering the elevator with respect to the carriage.

4. In transporting and dumping equipment for a dump- -ing container having a bail thereon for holding the container in place during dumping, of a pair of forks adapted for supporting engagement with the container, hoisting means for the forks, a carriage mounted in fixed relation to the forks and extending in upright position, an elevator mounted on the carriage for raising and lowering movements with respect thereto, a dumping hook on the elevator in position for lowering movement to a point below the carriage and for engagement with the bail to cause dumping action of the container, said carriage including a pair of upright guide channels spaced apart transversely and mounting the elevator therebetween, said guide channels having the lower ends thereof open for projecting action of the elevator downwardly through said open lower end, said elevator including a pair of upright channels spaced apart in guiding relation with the carriage, a bar extending transversely of the upper end of the upright channels and secured thereto, said transverse channels extending to points beyond opposite sides of the carriage, upright cylinders mounted on the carriage and connected with the opposite ends of said transverse bar for raising and lowering the elevator with respect to the carriage, the

dumping hook being mounted between the upright bars of the elevator, and means journaling the hook to the upright bars for swinging movement with respect thereto. 5. In transporting and dumping equipment for a dumping container having a bail thereon adjacent the bottom of the container for holding the container in place during dumping, a carriage, hoisting means for the carriage, a pair of forks mounted in fixed relation to the carriage and adapted for supporting engagement with the container, an elevator mounted on the carriage for raising and lowering movements with respect thereto, an automatic dumping hook on the elevator in position for lowering movement to a point below the bail and for engagement with the bail to cause dumping action of the container, said carriage including a pair of upright guide bars spaced apart v ingY container having Ya bail thereon and lifting pins on its opposite ends for holding the container in place during dumping, a carriage, hoisting means for the carriage, a pair of forks mounted in fixed relation to the carriage and adapted for supporting engagement with said pins, an elevator mounted on the carriage for raising and lowering movements with respect thereto, an automatic dun-1p-V ing hook on the elevator in position for lowering movement to a point below the bail 'and for engagement with the bail to cause'dumping action of the container, said carriage including a pair'of upright guide bars spaced apart transversely and mounting' the elevator therebetween, said guide barsjh'aving the 'lowerends thereof open for projecting action of the-elevator downwardly through said open lower ends, and means operatively connected with the carriage for moving the hook topa point below the forks and bail on the container for clearing the hook from the bail.

7. In transporting and dumping equipment for a dumping container having a dumping bail thereon, selectively at the upper or lower portions of said container for holding the' container in'place during dumping, the combination of a pair of forks adapted for supporting engagement with the container, hoisting means for the forks, a carriage mounted in fixed relation to the forks and extending in upright position, an elevator mounted on the carriage for raising the lowering movements with respect thereto, upper and lower'automatic dumping hooks on the elevator for selective engagement-with the bail at the upper or lower portion of' the container, said carriage including a pair of upright guide bars` spaced apart trans-A versely and mounting they elevatorV therebetween, said guide bars having the lower ends thereof open for projecting action of the elevator downwardly through said open lower ends and means operatively connected with the carriage for selectively moving the hooks below the forks and moving the lower hook below the bottom of the carriage and bottom of the container for clearing the hooks from the bails.

8. In transporting and dumping equipment for a dumping container having a bail thereon for holding the container in place during dumping, of a pair of forks adapted for supporting engagement with the container, hoisting means for the forks, a carriage mounted in xed relation to the forks and extending in upright position, an elevator mounted on the carriage for raising and lowering movements with respect thereto, and a dumping hook on the elevator in position for lowering movement to a point below the carriage and 'for engagement with the bail to cause dumping action of the container, said carriage including a pair of upright guide bars spaced apart transversely and mounting the elevator therebetween, said guide bars having the lower ends thereof open for projecting action of the elevator downwardly through said open lower end.

9. In transporting and dumping equipment, the combination with a container having lifting pins connected with opposite end portions thereof and having a bail connected with the bottom portion of the container, of an upright hoisting carriage having arms connected therewith in positions for engaging the lifting pins to support the container, an upright elevator mounted for upward movement relative to the carriage, a dumping hook mounted on the elevator, and means mounting the elevator for raising and lowering movements with respect to the carriage and for lowering the elevator relative thereto to a position wherein the hook is lowered below the lifting arms.

10. In transporting and dumping equipment, the combination with a container having lifting pins connected with opposite end portions thereof and having a bail connected with the bottom portion of the container, of an upright hoisting carriage having arms connected therewith in positions for engaging the lifting pins to support the container, an upright elevator telescoped in the carriage, a dumping hook mounted on the lower end portion of the elevator, and means mounting the elevator forY raising and loweringf movements with respectto the car-y riage and for'lowering the elevator relative thereto toaposition wherein the' hook is` lowered below'the carriage, said hook having a closure shuttle thereon in position for automatic disengagement from the bail upon lowering movement of the hook to a pointv appreciably belowY the. bail.

Vl1. In transporting and dumping equipment, the com-V bination with a dumping container having a bail thereon adjacent the bottom of the container and accessible at one side thereof, and lifting pins on the container at opposite ends thereof, Vof an upright mast, anf elevator mounted on the mast for-raising and lowering movements relative'thereto, means mounted on the elevator for engagement with the lifting pins to raise and lower ther container, a carriage mounted on the elevator for raising and lowering movements relative thereto, an automatic hook mounted on the carriage in the path ofthe ybail to engage with'the latter automatically, a shuttle over the hook to disengage the hook from the bail, andY means operatively connected with the carriage for moving the hook to a point below the bottom of the mast forclearing the hook from the bail. Y l

l2. In transporting and dumping equipment, the combination wit-h a dumping container having a bail thereon adjacent the bottom of the container and accessible at Y one side thereof, and lifting pins on the container` at opposite ends thereof, of an upright mast, an elevator mounted on the mast for raising and loweringvmovements relative thereto, means mounted on the elevator for engagement with the lifting pins to raise and lower the container, a carriage mounted on the elevator for raising and lowering movements relative thereto, an automatic hook mounted on the carriage and having an upturned hook portion projecting outwardly from the carriage in the path of the bail to engage with the latter automatically, a shuttle connected with the hook overlying the hook portion for conining the bail therein, and means operatively connected with the carriage for moving the hook to a point below the bottom of the mast for clearing the hookfrom the bail. Y Y

13; In transporting and dumping equipment for-a dumpVv ingcontainer having a dumping bail thereon selectively at the top or bottom' of said container, the combination of anupright mast', an elevator mounted on the maStfOr; raising and lowering movements relative thereto, fork arms onV the elevator in position for engaging and lifting'- the container, a carriage mounted on the elevator, auto matic hooks mounted on the carriage adiacent the top; and bottom thereof for selective engagement with the bail at the top or bottom of the container, each of the anto matic hooks having a shuttle thereover for disengagingthe hook from the bail, and means operatively connectedwithV the carriage for moving the lower hook to a point below the bottom of the mast. Y

' 14. In transporting and dumping equipment for a dumping container having a dumping bail thereon selectively at the top or bottom of said container, the combination with a container having lifting means at opposite ends thereof,.of an upper mast, an elevator mounted vupon themast for raising and lowering movements' relative there'- Vto, fork arms on the elevator in position for engaging the lifting means on the container at opposite ends thereof for lifting the container, a carriage mounted on the elevator, automatic hooks. mounted on the carriagek adjacent the top and bottomv thereof for selective engagement with the bail' at the top or bottom of the container, each of the automatic hooks having a shuttle thereover forv disengag-4 ing the hook from the bail, and vmeans operatively connected with the carriage for moving the lower hook to point below the bottomV of the mast.

References Cited in the file of this patent UNITED STATES PATENTS Herman Aug. 12, 1952 

